Contact holder for a socket or for a plug of an electrical connector

Abstract: The contact holder comprises a cylindrical body (2) of electrically insulating material formed with a plurality of seats (4, 6, 8) which can receive respective contacts (10). The body (2) has a first group of seats (4) located in a radial outer position and a second group of seats (6) located in a radially inner position. The body has an aperture (18) disposed in a radially inner position relative to the seats (4) of the first group. Each seat (6) of the second group communicates with the aperture (18) via a respective radial slot (20).

Description: The present invention relates to a contact holder for a socket or for a plug of a connector for electrically connecting a towing vehicle and a towed vehicle. More precisely, the invention relates to a contact holder of the type defined in the preamble of Claim 1, which is known from the document EP-A-0 444 478. The document EP-A-0 444 478 illustrates a contact holder comprising a cylindrical body of electrically insulating material formed with a plurality of seats (in this particular case thirteen) which can receive respective contacts. A first group of seats (in this particular case nine seats) is located in a radially outer position, the seats communicating with the circumferentially outer side of the body via respective radial slots. The contact holder body also has a group of seats disposed in a radially inner position. Each seat belonging to the radially inner group communicates with a respective seat of the outer group via a radial slot. In this way, each contact can be placed in the respective seat, whether it belongs to the inner group or to the outer group, by means of a radial movement relative to the body from the outer circumferential side. The correct arrangement of each contact must be checked when the contact holder has been provided with the contacts and with the corresponding conductors. If, when this is checked, it is noted that a contact is connected to the wrong conductor, it is necessary to disconnect the conductor and the contact but, in general, this is impossible if the contact in question is not removed. The principal disadvantage of the solution described in the above-mentioned document EP-A-0 444 478 consists in that, in order to remove any of the contacts located in the radially inner position, it is also necessary to remove the contact accommodated in the seat of the radially outer group communicating with the seat of the contact to be removed. The present invention has the object of providing a contact holder of the type defined initially which, in addition to enabling the contacts to be assembled rapidly in the respective seats, allows each contact to be removed independently of the others. In accordance with the present invention, this object is achieved by a contact holder having the characteristics forming the subject of the main claim. Further characteristics and advantages of the invention will become clear from the following detailed description, given purely by way of non-limiting example, with reference to the appended drawings, in which: Figure 1 is an exploded perspective view of a contact holder according to the present invention; Figure 2 is a view on the arrow II in Figure 1; and Figure 3 is a view similar to Figure 3, illustrating a variant of the contact holder according to the invention. Referring to Figures 1 and 2, a contact holder for a socket or for a plug of a connector for electrically connecting a towing vehicle and a towed vehicle is indicated 1. The contact holder 1 can, for example, equip the plug or socket of a connector of the type described in the Applicant's European patent application No. 0 544 630. The contact holder 1 comprises a cylindrical body 2 of moulded plastics material formed with a plurality of seats 4, 6 and 8 which can receive respective male or female contacts, depending on whether the contact holder 1 is intended to equip a plug or a socket. Figure 1 shows two male contacts 10, but it is evident that what has been described applies equally to female contacts. Referring in particular to Figure 2, the body 2 has a first group of seats 4 disposed in a radially outer position. The centres of the seats 4 all lie on a circumference centred on the axis of the cylindrical body 2 and having a radius R 1 . Each seat 4 of the outer group communicates with the outer circumferential side 12 of the body 2 via a respective radial slot 14. The body 2 has a second group of seats 6 located in a radially inner position. The centres of the seats 6 lie on a circumference with a radius R 2 < R 1 in which the difference between R 1 and R 2 is greater than the maximum diameter of each contact 10, indicated d 1 in Figure 1. The seats 6 of the second group communicate with a through aperture 18 in the body 2 via respective radial slots 20. A further seat 8 is disposed at a distance R 3 from the axis of the cylindrical body 2 which is intermediate between the distances R 1 and R 2 . The seat 8 communicates with the outer circumferential side 12 of the body 2 via a radial slot 22 and also communicates with the aperture 18 via a slot 24. Each seat 4, 6 has an arcuate profile of an extent greater than 180° and has a diameter d 2 such that it can receive, by snap engagement, an anchorage portion 26 of a respective contact (Figure 1). Referring to Figure 1, the anchorage portion 26 of each contact 10 is located between two annular collars 28, 30 which secure the contact 10 axially relative to the body 2 by frontal engagement with respective edges of the seats 4, 6 and 8. The contacts 10 are placed in the seats 4 of the radially outer group by means of a radial movement relative to the body from the outer circumferential side. The contacts 10 are likewise mounted in the seats 6 of the radially inner group by means of a movement of the contacts in the radial direction. However, on this occasion, the contacts are made to pass through the slots 22, 24 until they reach the aperture 18 through which the contacts are placed individually in the respective seats 6. In order to permit this manoeuvre, the aperture 18 defines an empty space with dimensions which are greater than the maximum diameter d 1 of each contact 10. In Figure 1, a part for the lateral retaining of the contacts 10, consisting of moulded plastics material and having a plurality of tubular passages 34 which can receive respective contacts 10, is indicated 32. In the case of a socket, the tubular passages 34 have lengths substantially equal to the lengths of the contacts 10, whilst, in the case of the plug, the tubular passages have lengths which are less than half the length of the contacts 10, such that one part of each contact projects from the front wall of the retaining part 32. The lateral retaining part 32 is provided with a plurality of resilient teeth 36 which are snap-engageable in respective anchorage seats 38 in the body 2 (Figure 2). Figure 3 illustrates a variant of the contact holder body 2. The parts identical to those described above are designated by the same reference numerals. In the variant of Figure 3, the through aperture 18 is closed around its entire periphery. In this case, the contacts which are to be mounted in the seats 6 of the radially inner group are inserted into the aperture 18 in the axial direction until the anchorage portion 26 is brought into correspondence with the respective seat 6 and are then placed in the seats by means of a movement in the radial direction.

Claims: A contact holder for a socket or for a plug of a connector for electrically connecting a towing vehicle and a towed vehicle, comprising a cylindrical body (2) of electrically insulating material formed with a plurality of seats (4, 6, 8) which can receive respective contacts (10), the body (2) having a first group of seats (4) located in a radially outer position and a second group of seats (6) located in a radially inner position, in which the seats (4) of the first group communicate with the outer circumferential side (12) of the body (2) via respective radial slots (14), such that the respective contacts (10) can be mounted from the outer circumferential side (12) by means of a radial movement relative to the body (2), characterized in that the cylindrical body comprises an aperture (18) disposed in a radially inner position relative to the seats (6) of the second group; and in that the seats (6) of the second group communicate with said aperture (18) via respective radial slots (20). A contact holder according to Claim 1, characterized in that said aperture (18) is closed around its entire periphery. A contact holder according to Claim 1, characterized in that said aperture (18) communicates with the outer circumferential side (12) of the body (2) via a radial slot (22, 24) which allows the passage of the contacts (10) by means of a radial movement relative to the body (2). A contact holder according to Claim 3, characterized in that it comprises a further seat (8) disposed in an intermediate position between the seats (6) of the inner group and those of the outer group and communicating via said respective radial slots (24, 22) with the aperture (18) of the body (2) and with the outer circumferential side (12) of the body (2). A contact holder according to Claim 1, characterized in that the aperture (18) defines a useful manoeuvring space of dimensions which are greater than the maximum diameter (d 1 ) of each contact (10). A contact holder according to Claim 1, characterized in that each seat (4,6) of the first and second group has an arcuate profile of an extent greater than 180° and has a diameter (d 2 ) such that it can receive an anchorage portion (26) of a respective contact, said anchorage portion (26) will engage a respective seat (4, 6) by snap engagement, and said anchorage portion is located between a pair of annular collars (28, 30) which will secure the contact (10) axially relative to the body (2) by frontal engagement with respective edges of the seat (4, 6). A contact holder according to Claim 1, characterized in that it comprises a part (32) for the lateral retaining of the contacts (10), which part is provided with a plurality of tubular passages (34) which can receive respective contacts (10) and with means (36) for snap engagement with said cylindrical body (2).

Inventors: PASOTTO GIORGIO, PASOTTO, GIORGIO
Applicants: MENBER S SPA, MENBER'S S.P.A.
Application year: 1994
Main classification: H01R13
IPC codes: H01R24, H01R13